It has been proposed previously to provide a steering wheel unit for use in a motor vehicle. The steering wheel is mounted to rotate relative to a fixed housing. The axis about which the steering wheel rotates is offset from the axis of the steering column. The steering column carries a pinion gear. The steering wheel carries a ring gear which meshes with part of the pinion gear. As the steering wheel rotates, so the steering column is rotated.
In one embodiment of a steering wheel of this type, it is possible to mount a central air-bag unit, with the air-bag unit remaining stationary while the steering wheel rotates. This enables a specially shaped air-bag to be utilized and also facilities the mounting of control buttons or the like on the upper surface of the air-bag unit.
It has been found that with a steering wheel of this type, there may be some “play” between the pinion on the steering column and the ring gear provided on the steering wheel. This gives the steering wheel an undesirable “feel” when the motor vehicle is being driven.